Javascript：如何用键值对作为字符串从 object 创建数组？

Question

I have an object, from which an array has to be made, where key + value pairs are converted to strings.

var obj = {'x': 1, 'y': 2, 'z':3};

I have tried to convert the content to strings:

var joined = Object.entries(obj ).join(' ');

"x,1 y,2 z,3"

and to an array of arrays

var entries = Object.entries(obj);

But it is not exactly what I need

My ideal result is

var arrayFromObject = ['x 1', 'y 2', 'z 3'];

I can probably flatten the array of arrays but maybe there is a better solution?

Answer 1

You can get the desired output using .map() , .join() and Object.entries() :

• Get an array of [key, value] pairs of a given object's properties using Object.entries() .
• Iterate using .map() over the array values returned in first step and use .join() to get the string in desired format.

 const obj = {'x': 1, 'y': 2, 'z': 3}; const array = Object.entries(obj).map(a => a.join(' ')); console.log(array);

Answer 2

If you know you have a KVP set, you can do something like

const obj = {'x': 1, 'y': 2, 'z':3};
const result = Object.entries(obj).map(entry => `${entry[0]} ${entry[1]}`);
//(3) ["x 1", "y 2", "z 3"]

Answer 3

Object.keys(obj).map(x => `${x} ${obj[x]}`)

Explanation

Object.keys(obj) returns ["x", "y", "z"] and map then maps every key to a template literal ${x} ${obj[x]} where obj[x] is the value ( y is mapped to y 2 )

Answer 4

 const obj = {'x': 1, 'y': 2, 'z':3}; const array = Object.entries(obj).map(a => a.join(' ')); console.log(array);

Answer 5

You can use for loop for your desired output, you could've used map but it creates performance issues if the list is large.

 let obj = { x: 1, y: 2, z: 3 }; let outputArray = []; for (let i = 0; i < Object.keys(obj).length; i++) { outputArray.push(Object.keys(obj)[i]+' '+Object.values(obj)[i]); } console.log(outputArray);